Hammer drill



Aug. 7, 1951 E, TOPANELIAN, .JJR

HAMMER DRILL TOPANELIAN R- BY I, 6 21 ha $3 4 m 5 Q N 1 Filed Oct. 28, 1948 ATTO RNEY Patented Aug. 7, 1951 to Gulf Research & Development Company, Pittsburgh, Pa., a corporation of Delaware Application Dctober 28, 1948, Serial No. 57,035

3 Claims. (Cl. 255-4. 1)

This invention relates to a Well drill and more particularly to an impact-type well drill having an impact frequency which may be controlled by varying the speed of rotation of the drill pipe and drill casing.

Common impact-type well drills are, generally speaking, rather inflexible from the standpoint of impact frequency. The impact frequency of such drills is generally fixed and uncontrollable once operation of the drill has commenced. Obvious- 1y, this does not permit of optimum drilling efiiciency when it is recognized that a number of vastly different types of formations are usually encountered by a drill in every drilling operation. :Accordingly; the primary object accomplished by my invention is the provision of an impact or -'hammer-type well drill having an impact frequency which may be controlled by varying the speed of rotation of the drill pipe. A further object accomplished by my invention is the provision of a well drill which is capable of automatically shutting off when drilling off or "lowering the drill into the well.

A still further object accomplished by my in-- vention is the provision of a drill of the character described capable of being closely controlled by the operators at the surface above the well.

These and other useful objects are accomplished by my invention as disclosed in this speci- .fication of which the accompanying drawings form a part. My invention is exemplified in the drawings and the descriptive matter relating Figs. 1 and 2;

Fig. 4 is a transverse sectional view taken along line 4-4 of Fig. 1;

Fig. 5 is a transverse sectional view taken along :line 5-5 of Fig. 2;

Fig. 6 is a transverse sectional view taken alon line 66 of Fig. 2; and

Fig. 7 is a transverse sectional view taken along line 1-1 of Fig. 2. i

Referring to the drawings, and particularly to Fig. 1, item I is an adapter piece provided with a tapered standard drill-pipe thread at its upper end to facilitate attachment to a drill stem or a drillcollar (not shown), and is further provided witha passage} for conducting drilling fluid operation of the drill.

adapter I is attached to a piston chamber hous- I therethrough into the drill mechanism. An orifice 3 may be inserted in adapter I to provide-a by-pass which will bleed off drilling fluid if full pressure of the drilling fluid is not required for The lower portion of ing or casing 4 which in turn is connected therebelow to a coupling piece 5. A cylinder block-6 is disposed within casing 4 and constrained from movement by adapter I and coupling 5 exerting pressure on-the ends thereof. The purpose of cylinder block 6 is to accommodate a piston "I which is adapted through piston rod 8 to reciprocate a hammer 9 (shown in Fig. 2), said hammer being the means provided to produce percussive blows on the drill bit.- The upper portion of cylinder block 6 is sealed off by means such as plug I0 welded thereto so that a chamber H is formed above piston I. The outer portion of cylinder block-6 is adapted to'form sediment traps I2 which are connected to chamber I I by passages I3. The upper end of cylinder block 6 forming chamber H is provided with a small passage I3a similar to a keyway to permit a controlled release of fluid from the dashpot pocket formed in the upper end of cylinder 6 when piston I is elevated past the passages l3. The sediment traps I2 are connected to the well bore by means of passages I4 in casing 4 located below passages I3 of the cylindergblock. The portions of cylinder block 6 adjacent sediment traps I'2 are faced with metal strips I5 welded thereto and overlapping weld beads IS in passages I4 to provide a complete liquid seal between the sediment trapsa'nd other portions of the drill, as shown in Fig. 4.

The uppermost portion of cylinder block 6 above plug It) forms a chamber l'l connecting with passage 2. This chamber further connects through passages I'8 withpassages l9 formed between cylinder block .6 and easing 4. Passages I9 'further connect through passages of the cylinder block to passage ZI defined by the annular space between coupling 5 and piston rod 8.

Continuing to Fig. 2,'the lower portion of coupling 5 is attached by means of threads to an upper guide casing 22 to provide a guiding surthree sets of guide strips 23 and 24 on hammer 9.7 .A lower. main housingor casing 21 is attachedby means of threads to upper guide casing 22 and a collar 28 Welded to casing 22 provides a seal against the face of casing 21. The lowermost portion of casing 21, shown in Fig. 3, is threaded to receive a guide bushing 29 having a straight bore 30 and a tapered portion 3|. The function of this guide bushing is to act as a lower guide for a bitstem 32 which in turn has a straight portion 33 and a tapered portion 34 adapted to slidably match and cooperate with the corresponding portions of guide bushing 29. Bit-stem 32 contains a central passage 35 for flushing fluid and this passage connects with the central passage 36 of a conventional bit 3'! which is attached to the lowermost portion of bit-stem 32 by means of threads 38. Bit 3'! is constructed to permit the passage of flushing fluid from central passage 36 through passages 39 into the Well bore so that chips may be washed from the hole in the conventional manner. While I have shown a fish tail type of bit" for purposes of illustration other types such as conventional roller bits may alternatively be used. Such roller bits also have central passages for flushing chips from the hole.

The upper portion of bit-stem 32, shown in Fig. 2, is welded to a valve-facing piece 40 containing a port 4! connecting through passages 42 and 43'to central passage 35 in bit-stem 32. A sleeve 44 pressed about valve-facing piece 40 and the upper portion of'bit-stem 32' acts as a further guide for the longitudinal movement of bit-stem 32, said sleeve 44 having a close slid'able fit with casing 2T. A rotatable valve 45 is situated immediately above valve-facing piece 40. This valve,

shown also in Figs. 6 and '7, is keyed to casing 21 by means of keys 46 and Reyways 41 so that valve 45 willrotate with casing 21 and with respect to valve-facing piece 40, and in addition, so that valve 45 with keys 46 may be slidably moved in casing 2'1. Valve 45 is provided with a valve port 48 which during rotation of the drill stem is periodically connected with port 41 of valve facing piece 40 Port 48, however, is always connecting with passage 49 thereabove containing operating fluid under pressure. 45 considered with valvefacing piece 40 and bitstem 32 comprises an anvil which will transmit percussive blows exerted by the hammer 9 there- 7 onto bit 31 and the formation in the well.

"To render the drill inoperative when circulat- "ing' in or lower the drill into the well and to permit what is commonly known as drilling off,

in its lowermost position. These passages to provide a relief for operating fluid under pressure when the valve and bit-stem are in the position as shown so that hammer 9 cannot be elevated by pressure fluid. Since both bit-stem 3-2 and valve 45 are capable of longitudinal movement with respect to casing2'l', passages 50 will become sealed off by valve 45 when the bit rests against a formation and the casing 2T is .further lowered aboutvalve 45: and bit-stem 32. This permits operating fluid: pressure to build up beneath hammer 9 and piston I- rendering the drill operative and permitting the hammer to. be elevated for a percussivebl'ow.

The size of' port 48' in valve 45 and the size of ports 41 and 42 in valve-facing piece 40 and bitstem 32 may vary considerably. However, port 4& may advantageously be defined by an 80 sec- "tor of valve 45 and ports 4|. and 42 may advantageously. he a 120 sector, so that when the casing is rotated, valve 45swi11 beclosed duringabout It is apparent that valve of rotation and open during about 200 of rotation.

It is customary when operating deep well drills to first rotate in or circulate in the well drill. This simply consists in establishing the circulation of operating fluid through the drill and into the well while rotating and lowering both the casing and drill in the well. Such a procedure would be accomplished by my drill in the following manner: Assuming the unit to be suspended vertically with the upper end of adapter I attached to a drill pipe, all loose parts will be free to assume their lowermost positions, such positions being as shown in the drawings. For example, bit-stem 32 will tend to rest with the taper 34 in contact with taper 3| in guide bushing 29 and the top of bit 31 Will be some distance below bushing 29. Valve 45 will be resting on top of valve-facing piece 40 and hammer 9 will be in contact with the upper face of the valve, piston I also being in its lowermost position. Fluid may then be circulated through passages 2, l1, [-8, l3, 20,2l, 25, 26 and 49, and out through passages 50 in casing 21, regardless of whether the port in the valve and the port in the bit-stem are in register or not. If ports 48 and 4| are in register, drilling fluid may also circulate therethrough and through passages 42, 43, 35, 36, 39 and out into the well bore. This free circulation of fluid from beneath hammer 9 into the well prevents fluid pressure from building up suflicicntly to raise-the hammer. Thus, the position of the parts may be considered as a safety position which prevents hammer operation whenever the parts become .so arranged. Owing to the friction between bit-stem 32 and guide bushing 29 in this position, the bit will be rotated along with the casing during this rotating, in period. At the same time, fluid from the well bore will enter through. passages. [-4 in the casing and proceed through passages 12 and I3 into chamber H above, the piston. This serves to balance the pressures of the inner and outer columns of fluid on the top andbottom-o-f piston 1.

When the bottom of the hole has been reached, the hammer mechanism will. begin to function to produce percussive blows on valve 45, bit-stem 3 2. and bit 3'! which transmits the blows to the formation. This phase of operation will be as follows: Since the bit 31- is constrained from downward movement by the formation at the bottom of the well, further lowering of the drill pipe will result in a lowering of casing 21 about bitstem 32 and valve 45, causing disengagement of the tapered portions 3| and 34 of guide bushing 29 and bit-stem 32, respectively. In other words, the bit-stem may be considered as moving relatively upwardv in the casing carrying valve 45 with it, so that shortly after bit 3.1: strikes the bottom of the well, valve 45 will be caused to slide upward and cover relief ports 50 in casing 2'l causing operating fluid pressureto build up beneath hammer 9 and piston 1. Since the drill pipe and the drill casing are undergoing constant rotation, there will be relative movement between valve 45 which is keyed to the casing and bit-stem 32 as well as valve-facing piece. 40' due to the fact that the bit-stem and bit are resting on the formation, which creates a drag against bit rotation. Casing 2'! and bushing 29'wil1 therefore turn freely about the bit-stem and maintain the bit-stem in a vertical position due to the guiding action of bushing 29 and sleeve 44, at the same time permitting free vertical movement as the bit is driven downward. In this stage of operation of the the 'drill pipe and casing 21 may rest on the top -of bit 31 or may be suspended slightly thereabove. 'When valve port 45 is in register with ports 4| and 42 on'the bit-stem, free fluid flow will result through the bit and hammer 9 will rest against valve 45. However, when these ports are not in register, the pressure will build up in passages 49, 25, and 2!, causing a higher pressure to exist beneath piston than exists on top of the piston in chamber 5 I which is in communication with the well bore under static fluid pressure. This difference in pressure will cause piston 1, piston rod 3 and hammer 9 to be elevated, and

such a condition will exist as long as the valve portsare not in register. However, when rotation of valve $5 with casing 21 again brings the ports into register, the flow of fluid through the bit-stem' and out of the'bit ports will resume, causing the pressure beneaththe hammer to drop substantially. Thus, the pressure on both sides piston will. become approximately equalized, permitting the hammer to fall under the gravitational forces acting thereon. .Ham

'mer 9 will then strike valve 45 with considerable impact, imparting a shock thereto which is transmitted through the bit-stem and bit to the for mation. Drilling of the formation is accomplished by the repetition of these blows and the progressive rotation of bit 3'! due to the gradual drifting of the bit. This drifting is possible since there is very little hydraulic pressure on the bitstem during the fall of the hammer, leaving it relatively free to drift during this time interval.

If the weight of the drill pipe and drill casing is allowed to rest on the bit it will automatically follow the bit downward. during a drilling operation. However, if the drill pipe and casing at tached thereto are suspended and remain fixed for a period, of time, the bit may be allowed to drill off or continue downward to the extent of its possible travel, whereupon operation will cease due to the exposure of relief passages 50.

It is apparent that complete control of the frequency of hammer impact may be had by simply controlling the speed of rotation of the drill pipe. It is therefore possible to select the most advantageous impact frequency for a given formation undergoing the drilling operation. Another advantage of my drill is that relatively little wear on the cutting edge of the bit is produced because of the very little rotation of the bit against the formation and the light weight on the bit when it is not being struck by the hammer. My drill is further advantageous in that automatic control of its operation is provided whereby hammering will be prevented while lowering the drill into the well and operation will automatically cease if the casing is suspended and the bit and bit-stem are permitted to drill off. Other advantages lie in the novel construction and ar rangement of parts which permits easy replacement and economic manufacture as well as efrl cient operation. The simplicity of construction extends the operational life before replacements are necessary. Furthermore my invention provides a drill which permits maximum utilization of fluid pressure.

It will be apparent to those skilled in the art who have familiarized themselves with this disclosure of my invention that numerous modifications thereof may be made without departing from the spirit thereof. For example, in most instances the number of passages used for operating fluid are not critical. Rather, the volume of fluid capable of being accommodated by such passages is the controlling factor in determining their number and size. The'valve 45 and valvefacing piece 4!), together with bit-stem 32 may be provided with more than one passage to further control the frequency of the hammer stroke. The embodiment illustrated in the drawings is entirely lacking in any kind of spring, but should it be desirable to increase the impact force of the hammer a spring may be employed above the hammer to return it with greater force and in shorter time. When such a spring is used above the hammer it becomes desirable to shorten the valve ports so that the open register time will be correspondingly decreased.

The preferred embodiment specifically shown and described herein is intended to be merely illustrative of my invention and in no manner should it be considered as a limitation thereof or as limiting the scope of the appended claims hereinafter made.

What I claim is:

l. A fluid-operated rotary reciprocating drilling mechanism comprising a cylindrical hollow casing adapted to be rotated and supplied with operating fluid under pressure, a bit-stem sealed to said casing and free to turn and slide therein and extending below the lower end thereof, said bit-stem having a longitudinal passageway therethrough with an eccentric opening on the upper face of said bit-stem, an anvil sealed to said casing and slidably disposed in and adapted to rotate with said casing above said bit-stem, a longitudinal passageway through said anvil with an eccentric opening on the lower face of said anvil, a reciprocable hammer freely sliding in said casing above said anvil, a cylinder attached to said casing and with its upper end open to the exterior of said casing and with its lower end open to the interior of said casing, an upward-extending plunger attached to said hammer and entering the lower end of said cylinder, and a passageway by-passing said cylinder to permit operating fiuid access to the lower end of said hammer to elevate the same whenever said openings in said anvil and said bit-stem are not in register.

2. A fluid-operated rotary reciprocating drilling mechanism comprising a cylindrical hollow casing adapted to be rotated and supplied with operating fluid under pressure, a bit-stem sealed to said casing and free to turn and slide therein and extending below the lower end thereof, said bit-stem having a longitudinal passageway therethrough with an eccentric opening on the upper face of said bit-stem, an anvil above said bit-stem sealed to said casing and having limited sliding movement therein and adapted to rotate with said casing, a longitudinal passageway through said anvil with an eccentric opening on the lower face of said anvil, a passageway through the wall of said casing proximate the lower limit of the top of said anvil and adapted to become obstructed upon upward movement of said anvil, a reciprocable hammer freely sliding in said casing above said anvil, a cylinder attached to said casing and with its upper end open to the exterior of said casing and with its lower end open to the interior of said casing, an upward-extending plunger attached to said hammer and entering the lower end of said cylinder, and a passageway by-passing said cylinder to permit operating fluid access to the lower end of said hammer to elevate the same whenever said openings in said anvil and said bit-stem are not in register.

2&6635983 3. A fluid-operated rotary reciprocating drilling mechanism comprising a cylindrical hollow casing adapted to be rotated and supplied with operating fluid under pressure, a bit-stem sealed to said casing and free to turn and slide therein and extending below the lower end thereof, said bit-stem having a longitudinal passageway therethrough with an eccentric opening on the upper face of said bit-stem, means limiting the downward movement of said bit-stem with respect to said casing, means engaging said casing and said bit-stem to prevent relative rotation therebetween when the latter is at its lower limit, an anvil sealed to said casing and slidably disposed in and adapted to rotate with said casing above said bit-stem, a longitudinal passageway through said anvil with an eccentric opening on the lower face of said anvil, a reciprocable hammer freely sliding in said casing above said anvil, a cylinder attached to said casing and with its upper end 20 open to the exterior of said casing and with its lower end open to the interior of said casing, an upward-extending plunger attached to said hammer and entering the lower end of said cylinder,

8 and a passageway by-passing said cylinder to permit operating fluid access to the lower end of said hammer to elevate the same whenever said openings in said anvil and said bit-stem are not in register.

EDWARD TOPANELIAN, JR.

REFERENCES CITED 2 The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,065,298 Currell June 17, 1913 1,861,042 Zublin May 31, 1932 1,881,258 Bayles Oct. 4, 1932 1,891,416 Harris Dec. 20, 1932 1,892,517 Bennington Dec. 27, 1932 FOREIGN PATENTS Number Country Date 328,629 Great Britain Apr. 30, 1930 351,457 Italy Aug. 11, 1937 697,466 Germany Oct. 14, 1940 

